Plug

ABSTRACT

The invention relates to a plug ( 1 ), comprising a base body ( 3 ) and contact elements, running in the interior of the base body ( 3 ). On the opposing sides of the external wall of the base body ( 3 ), two wing-shaped connector elements ( 8 ) open out, which project over the rear side of the base body ( 3 ). The undersides of the connector elements ( 8 ) form contact surfaces for the production of soldered connections to a circuit board ( 2 ).

The invention relates to a plug in accordance with the preamble of claim 1.

Such plugs are used as electrical connections for electronic devices of all types in large numbers. In the course of miniaturization of such devices, the plugs of the devices are applied directly on the printed circuit boards upon which the electronic components of such devices are arranged.

The printed circuit boards which can be especially formed of multilayer circuit boards, have a high packing density of their conductive tracks and components. The electronic components are applied to the respective printed circuit boards by means of mounting automatons automatically and are there soldered in place. The production of such assemblies is referred to as the SMD (Surface Mounting Device) technique.

With this technique at low fabrication cost, complex arrangements of components on printed circuit boards can be fabricated in arrangements of relative small size.

It is, however, a problem to integrate plugs in this kind of fabrication process. The use of plugs as SMD components is indeed basically known, but the automatic application of such plugs and their connection to the conductors of the printed circuit board is associated with significant drawbacks because of the relative sizes of such plugs. As a consequence, such plugs are typically soldered by hand to the printed circuit boards, which undesirably increases the fabrication costs of such devices. A further significant problem resides in that application of such plugs to the printed circuit board should be capable of insuring that the unit which is thus formed will have the smallest possible size.

The invention has as its object to so form a plug of the type described at the outset so that it can be applied to a printed circuit board in the most rational and space-saving manner possible.

This object is attained by the features of claim 1. Advantageous embodiments and preferably features of the invention are described in the dependent claims.

The plug according to the invention has a base body and contact elements which extend into the exterior of the base body. At opposite sides of the outer wall of the base body, two wing-shaped connector elements open outwardly. These connector elements project over the rear side of the base body whereby their undersides form contact surfaces for producing solder connections to a printed circuit board. The connector elements provided on the plug according to the invention serve to enable establishment of a solder connection with the respective printed circuit board which forms a ground connection of the plug. Because of the large area configuration of the contact surface which is seated directly on the printed circuit board, an especially good ground connection of the plug is obtained.

Furthermore, with the connector elements, good mechanical retention of the plug upon the board can be obtained. The plug can thus be positioned on the board by means of an automated mounting machine as an SMD component reliably in a precise position.

Since the connector elements open laterally at the base body of the plug, the base body projects both upwardly and also downwardly beyond the connector elements. This means that the plug can be mounted on the board to lie more deeply than plugs have been positioned otherwise so that the spatial requirements for the plug can be held exceptionally small.

The undersides of the connector elements of the plug thus extend in a connecting plane in which preferably the underside of an internal conductor extending over the back side of the plug also lies. This internal conductor can be soldered together with the contact surfaces of the connecting elements to the respective board by means of an automated soldering process. This soldering process can be carried out especially effectively in an automated finishing step.

In an especially preferred embodiment, the connector elements close against outer walls in regions of the rear segment of the base body, whereby the rear segments are disposed in a cutout or recess of the board. The size of the cutout is matched to the shape of the rear segment. In this manner an especially space-saving application of the plug to the board is achieved. In addition, the plug is positionable precisely in the cutout and thus is exactly positionable using the cutout on the board. Finally by an appropriate choice of the lengths of the connector elements, the plug can be secured upon the board against tilting since the center of gravity of the plug lies upon the board. In this manner dislocation of the plug with respect to the seat upon the board can be avoided.

A precondition for this aspect of the invention is however a certain minimum length of the connector elements. A greater length of the connector elements results however in an undesirable increase in the weight of the plug.

In an especially advantageous embodiment of the plug according to the invention, the base body has shoulders which extend like the connector elements on oppositely disposed sides of the outer wall of the base body. The shoulders have bearing surfaces which lie in the same connecting plane as the contact surfaces. Preferably the shoulders extend over the entire length of the base body.

During the mounting process, the plug is seated on at least one board, whereby in this case not only the contact surfaces of the connector elements but also the bearing surfaces of the shoulders lie upon the upper surface of the board. Thus even for the case in which the connector elements have only a minimum length, a reliable position-exact retention of the plug upon the board on which it is seated can be obtained.

The boards are arranged during the mounting process in multiples for so-called multiple uses. Depending upon the arrangement of the boards, the connecting elements and shoulders of a plug can be caused to rest upon one board or upon two mutually abutting boards. In the case in which the shoulders and connecting elements rest upon different boards as a result of the mounting at the edge of the board in which the recess for receiving the rear segments of the base body is provided, a segment can be connected to a second board with additional board material upon which the shoulders of the plug mounting upon the first board can rest. This additional board material can serve alone for position stabilization of the plug during the mounting process and during the soldering process. After the soldering process has terminated, the additional board material can be removed from the second board.

The invention will be further described based upon the drawings. They show:

FIG. 1 a schematic illustration of an embodiment of a plug according to the invention mounted upon a printed circuit board.

FIG. 2 a side view of the arrangement according to FIG. 1.

FIG. 3 a cross section through the arrangement according to FIG. 2.

FIG. 4 a plan view of the board according to FIG. 1 without a plug.

FIGS. 1-3 show an embodiment of the plug 1 according to the invention which is mounted on a printed circuit board 2 as an SMD (Surface Mounting Device) component. The printed circuit board 2, which, for example, is constituted as a multilayer board with different conductive patterns in which layer, has only been shown fragmentarily in the Figures and in a schematic form. The plug 1 according to the invention or a multiplicity of such plugs 1, are mounted on the board 2 by means of an automated mounting machine or mounting automaton such that an automated soldering connection can also be formed between the boards 2 and the plugs 1.

During this finishing step, the boards 2 are arranged in a multiple array, so-called multiple use. In FIGS. 1 and 4 the multiple arrangement is signified by two boards 2 and 2 a which border each other and abut at their longitudinal sides.

The plug 1 has a base body 3 which is comprised as a die cast or injection-molded part and has a substantially rotation symmetrical configuration with respect to its longitudinal axis. In the interior of the base body 3 there is an insulator 4 which preferably is comprised of a plastic. Additional components can also be located in the interior of the base body of the plug 1, especially contact elements. One of the contact elements is formed from an internal conductor 3 which extends through the center of the interior of the base body in its longitudinal direction and projects beyond the rear side of the base body 3.

On the upper side of the outer wall of the base body 3 there is located a detent nose 6 for fixing a socket member on the plug.

In addition on the upper side of the base body 3 there is a recess 7 which forms a so-called “pick'n place” surface. On the recess 7 the plug 1 can be fitted onto the mounting automaton for gripping thereby to place the plug 1 upon the board 2. The plug 1 has two wings-shaped connecting elements 8 which open outwardly on opposite sides of the outer wall of the base body 3. The identically configured connecting elements 8 have a rectangular contour and are formed in one piece with the base body 3. The connecting elements 8 have a constant rectangular cross section over their entire lengths.

As is especially visible from FIG. 1, the connecting elements 8 enclose in the region of a rear segment of the base body 3 laterally against the outer wall thereof. As a result, the front ends of the connecting element 8 project beyond the rear side of the base body 3.

The planar undersides of the connecting element 8 form contact surfaces and extend in a horizontal connecting plane. In this connecting plane the underside of the inner conductor 5, which also forms a contact surface, likewise runs.

To mount the plug on the board 2, the plug 1 is so placed on the board 2 that the contact surfaces of the connecting elements 8 and the inner conductor 5 rest upon the upper surface of the board 2 and can be soldered thereto. The solder locations on the contact surfaces of the connecting elements 8 form the ground connection of the plug 1.

As is especially visible from FIG. 4, the board 2, upon which the plug 1 is mounted, has a rectangular cutout 9 which opens at the front edge of the board 2. The plug 1 is seated on the board 2 from above so that the rear segment of the base body 3 lies in the cutout 9. Since the connecting elements 8 only project laterally from the outer wall of the base body 3 in the region of the rear segment, these connecting elements 8, when the rear segment lies in the cutout 9, rest with their entire surfaces on the board 2. The rear edges of the connecting elements 8 thus terminate flush with the edge of the board 2. The cutout 9 is matched to the shape of the front segment so that this is received without play in the cutout 9. In this manner an exact positioning of the plug 1 on the printed circuit board 2 is ensured. Since the plug 1 is itself recessed in the cutout 9, it only contributes to the occupation of a small amount of space.

As is especially visible from FIGS. 2 and 3, positioning pins 10 project from the undersides of the connecting elements 8. Upon setting of the plug 1 on the board 2, the positioning pins 10 pass through holes in the board 2. This gives rise to an improved positioning precision of the plug 1 on the positioning precision of the plug 1 on the board 2 and in addition to a position stabilizer of the plug 1.

Basically the connecting elements 8 should extend beyond the back side of the base body 3 that the center of gravity of the plug 1 lies upon the board 2 and thus ensures that the plug 1 can be secured against tilting relative to the board 2.

In the present case, the lengths of the connecting elements 8 can be shorter so that they alone cannot ensure a secure retention of the plug on the board 2.

For further stabilization of the plug 1 on the board 2, shoulders 11 are provided which are arranged on opposite sides of the outer wall of the base body 3.

As will be apparent from FIGS. 2 and 3, the shoulders 11 lie at the level of the connecting elements 8. The shoulder 11 can thus have horizontally extending bearing surfaces with which the shoulders 11 rest upon the board 2 from above. The bearing surfaces lie in the connection plane in which the contact surfaces of the connecting elements 8 also lie. As can be seen from FIGS. 2 and 3, the bearing surfaces extend directly into the associated contact surfaces.

As can be seen from FIG. 3, the base body 3 has a substantially hollow cylindrical shape. The wall thickness of the base body 3 in the region above the connection plane is somewhat larger than in the region below the connection plane. Thus the portion of the base body 3 lying above the connection plane forms a cylindrical element whose outer diameter is larger than that of the cylindrical element which forms the portion of the base body 3 below the connection plane. The bounding surfaces between these two portions form the shoulders 11 with their planar bearing surfaces.

For position stabilization of the plug 1, the shoulders 11 lie upon the edges of the board 2. In the simplest case, the shoulders 11 of the base body 3 rest upon the same board 2 upon which the connecting elements 8 of the base body 3 also lie and to which the plug 1 is fastened. In this case the cutout 9 and the board 2 are so dimensioned that the bearing surfaces of the shoulders 11 lie along its edges.

In an especially advantageous embodiment, the shoulders 11 lie upon a second board 2 a. This case has been illustrated in FIGS. 3 and 4.

The second board 2 a is connected to the front edge of the first board 2 at which the cutout for receiving the rear segment of the base body 3 opens. At the front edge of the second board 2 a, additional board material is connected and is joined with the second board 2 a along an intentional-break line S.

Additional board material is in the form of two mutually parallel lugs 12, 12 a. Between the lugs 12, 12 a lies an intervening space whose width is matched to that of the cutout 9 of the first board 2 and forms an extension of this cutout 9. The total length of the intervening space and the cutout 9 matches the total length of the plug 1.

To mount the plug, the plug is seated from above on the first board 2 so that its cutting element 8 rests upon the board 2 and the shoulders 11 lie upon the edges of the first board 2 in the rear segments of the latter bounding the cutout 9. The front regions of the shoulders 11 which are connected to the rear segment rest upon the lugs 12, 12 a of the additional board material. As a consequence the plug 1 is supported over the entire length of the shoulders 11 and the connecting elements 8 on supporting surfaces. The plug especially, is thereby secured against undesired tipping.

After the solder connection between the connecting elements 8 and the internal conductor 5 of the plug 1 on the one hand and the first board 2 on the other, the multiple use is separated and the individual boards are disconnected from one another. The additional board material is removed from the thus separated second board 2 a along the intentional break line S.

Reference Character List

(1) Plug

(2) First printed circuit board

(2 a) Second printed circuit board

(3) Base body

(4) Insulator

(5) Internal conductor

(6) Detent nose

(7) Recess

(8) Connecting element

(9) Cutout

(10) Positioning pin

(11) Shoulder

(12) Lug

(12 a) Lug

(S) Intentional break line 

1. A plug with a base body and contact elements in the interior of the base body, characterized in that on opposite sides of the outer wall of the base body (3) two wing-shaped connecting elements (8) open outwardly, which project over the rear side of the base body (3) whereby their undersides form contact surfaces for making solder connections upon a printed circuit board (2).
 2. The plug according to claim 1, characterized in that the solder connection between a connecting element (8) and the board (2) forms a ground connection.
 3. The plug according to claim 1 characterized in that as the contact element, an internal conductor (5) is provided which extends beyond the backside of the base body (3) and is solderable upon the printed circuit board (2).
 4. The plug according to claim 3 characterized in that the internal conductor runs through the center of the base body (3) in its longitudinal direction and in that the contact surfaces of the connecting elements (8) and the contact surfaces formed by the internal conductor (5) which are solderable to the board (2) lie in a connection plane.
 5. The plug according to claim 1 characterized in that the connecting elements (8) are formed in one piece with the base body (3).
 6. The plug according to claim 1 characterized in that the connecting elements (8) have identical configurations.
 7. The plug according to claim 1 characterized in that the connecting elements (8) each have a rectangular contour.
 8. The plug according to claim 1 characterized in that the connecting elements (8) in the region of a rear segment of the base body (3) close on its outer wall whereby the rear segment lies in a cutout (9) of the board (2).
 9. The plug according to claim 1 characterized in that from the underside of each connecting element (8) at least one positioning pin (10) projects and is engageable in a respective board in the board (2).
 10. The plug according to claim 9 characterized in that the base body (3) on opposite sides of its outer wall has a shoulder (11) which extends in the longitudinal direction of the base body (3) and by means of which the base body (3) can be seated in a recess (9) of a board (2).
 11. The plug according to claim 10 characterized in that the resting surfaces of the shoulders (11) which lie upon the board (2) lie in the connecting plane.
 12. The plug according to claim 11 characterized in that the resting surface of a shoulder (11) is connected to the contact surface of a connecting element (8).
 13. The plug according to claim 10 characterized in that the shoulders (11) extend the full length of the base body (3).
 14. The plug according to claim 1, characterized in that the base body (3) has a substantially rotationally symmetrical configuration with respect to its longitudinal access.
 15. The plug according to claim 14 characterized in that the portion of the base body (3) which lies below the connecting plane forms a first substantially cylindrical element with a first outer diameter and the portion of the base body (3) which lies above the connecting plane forms a substantially cylindrical second element with a second outer diameter which is larger than the first outer diameter and in that the bounding surface between the first and second cylindrical element lies in the connecting plane and forms the shoulders (11).
 16. The plug according to claim 10, characterized in that the shoulders (11) and the connecting elements (8) lie upon the same board (2).
 17. The plug according to claim 10, characterized in that the shoulder (11) and the connecting element (8) lie upon different boards (2, 2 a).
 18. The plug according to claim 17 characterized in that the second board (2 a) has additional board material for receiving the shoulders (11).
 19. The plug according to claim 18 characterized in that for producing the solder connection between the connecting elements (8) and the first board (2) the additional board material is separable from the second board (2 a).
 20. The plug according to claim 14, characterized in that on the upper side of the base body (3) a recess (7) is provided by which the plug can be gripped by a mounting or automaton for placing the plug on a printed circuit board (2). 